Glissa, the Traitor is a mythic Legendary Creature — Phyrexian Zombie Elf card from Commander's Arsenal Oversized (OCM1), collector number 3. Current market price: — (foil $4.81), TCGplayer market prices via Scryfall.
First strike, deathtouch Whenever a creature an opponent controls dies, you may return target artifact card from your graveyard to your hand.